Extremely high frequency (ehf) distributed antenna systems, and related components and methods

ABSTRACT

Extremely High Frequency (EHF) distributed antenna systems and related components and methods are disclosed. In one embodiment, a base unit for distributing EHF modulated data signals to a RAU(s) is provided. The base unit includes a downlink data source input configured to receive downlink electrical data signal(s) from a data source. The base unit also includes an E-O converter configured to convert downlink electrical data signal(s) into downlink optical data signal(s). The base unit also includes an oscillator configured to generate an electrical carrier signal at a center frequency in the EHF band. The base unit also includes a modulator configured to combine the downlink optical data signal(s) with the electrical carrier signal to form downlink modulated optical signal(s) comprising a downlink optical data signal(s) modulated at the center frequency of the electrical carrier signal. The modulator is further configured to send the downlink modulated optical signal to the RAU(s).

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/300,541, filed Jun. 10, 2014, which is a continuation of and claimsthe benefit of priority under 35 U. S. C. §365 of International PatentApplication No. PCT/US11/64428, filed on Dec. 12, 2011, the contents ofboth applications being hereby incorporated herein by reference in theirentireties.

BACKGROUND

1. Field of the Disclosure

The technology of the present disclosure relates to distribution ofradio-frequency (RF) communications signals in distributed antennasystem.

2. Technical Background

Wireless customers are demanding digital data services such as streamingvideo signals. Concurrently, some wireless customers use their wirelessdevices in areas that are poorly served by conventional cellularnetworks such as inside certain buildings or areas where there is littlecellular coverage. One response to the intersection of these twoconcerns has been the use of distributed antenna systems, which areespecially effective at providing wireless digital data services withina building. Such distributed antenna systems may use Wireless Fidelity(WiFi) or wireless local area networks (WLANs) to help provide digitaldata services.

However, WiFi and WLAN-based technology may not be able to providesufficient bandwidth for expected demand, especially as high definition(HD) video becomes more prevalent. As an example, people want to uploador download HD video on their mobile devices and current standards donot allow this without substantial degradation to the quality of thevideo.

SUMMARY OF THE DETAILED DESCRIPTION

Embodiments disclosed in the detailed description include extremely highfrequency (EHF) (i.e., 30-300 GHz), distributed antenna systems, andrelated components, and methods. The systems disclosed herein cansupport provision of digital data services to wireless clients. The useof the EHF band allows for the use of channels having a higherbandwidth, which in turn allows more data intensive signals to becommunicated without substantial degradation to the quality of thevideo. As a non-limiting example, the distributed antenna systemsdisclosed herein may operate at an EHF of approximately 60 GHz withapproximately 7 GHz bandwidth channels to provide greater bandwidth todigital data services. The distributed antenna systems disclosed hereinmay be well suited to be deployed in an indoor building or otherfacility for delivering of digital data services.

In this regard, in one embodiment, a base unit for distributing EHFmodulated data signals to at least one remote antenna unit (RAU) isdisclosed. The base unit comprises a downlink data source inputconfigured to receive a downlink electrical data signal from a datasource. The base unit further comprises an electrical-to-optical (E-O)converter configured to convert the downlink electrical data signal intoa downlink optical data signal. The base unit further comprises anoscillator configured to generate an electrical carrier signal at acenter frequency in the EHF band. The base unit further comprises amodulator. The modulator is configured to combine the downlink opticaldata signal with the electrical carrier signal to form a downlinkmodulated optical signal comprising the downlink optical data signalmodulated at the center frequency of the electrical carrier signal. Themodulator is further configured to send the downlink modulated opticalsignal to at least one RAU.

In another embodiment, a method for distributing EHF modulated datasignals to at least one RAU is provided. The method comprises receivinga downlink electrical data signal from a downlink data source. Themethod further comprises converting the downlink electrical data signalinto a downlink optical data signal. The method further comprisescombining the downlink optical data signal with an electrical carriersignal operating in the EHF band to form a downlink modulated opticalsignal comprising the downlink optical data signal modulated at thecenter frequency of the electrical carrier signal. The method furthercomprises sending the downlink modulated optical signal to the at leastone RAU.

In another embodiment, a system for distributing EHF modulated datasignals to at least one RAU is provided. The system comprises a downlinkdata source input configured to receive a downlink electrical datasignal from a data source. The system further comprises an E-O converterconfigured to convert the downlink electrical data signal into adownlink optical data signal. The system further comprises an oscillatorconfigured to generate an electrical carrier signal at a centerfrequency in the EHF band. The system further comprises a modulator. Themodulator is configured to combine the downlink optical data signal withthe electrical carrier signal to form a downlink modulated opticalsignal comprising the downlink optical data signal modulated at thecenter frequency of the electrical carrier signal. The system furthercomprises at least one RAU comprising an antenna. The at least one RAUis configured to receive the downlink modulated optical signal from themodulator, convert the downlink modulated optical signal to a downlinkmodulated electromagnetic signal, and transmit the downlink modulatedelectromagnetic signal to a wireless client.

In another embodiment, a base unit for distributing EHF modulated datasignals to at least one RAU is provided. The base unit comprises adownlink digital data source input configured to receive a downlinkelectrical digital data signal from a data source. The base unit furthercomprises an E-O converter configured to convert the downlink electricaldigital data signal into a downlink optical digital data signal, whereinthe E-O converter comprises a laser diode. The base unit furthercomprises a local oscillator configured to generate an electricalcarrier signal at a center frequency at approximately sixty (60)GigaHertz (GHz). The base unit further comprises a modulator. Themodulator is configured to combine the downlink optical digital datasignal with the electrical carrier signal to form a downlink modulatedoptical signal comprising the downlink optical digital data signalmodulated at the center frequency of the electrical carrier signal, themodulator further configured to send the downlink modulated opticalsignal to at least one RAU.

Non-limiting examples of digital data services include, but are notlimited to Ethernet, WLAN, Worldwide Interoperability for MicrowaveAccess (WiMax), Wireless Fidelity (WiFi), Digital Subscriber Line (DSL),Long Term Evolution (LTE), and high definition television signals, etc.Further, as a non-limiting example, the distributed antenna system maybe an optical fiber-based distributed antenna system, but such is notrequired. The embodiments disclosed herein are also applicable to otherremote antenna clusters and distributed antenna systems, including thosethat include other forms of communications media for distribution ofcommunications signals, including electrical conductors and wirelesstransmission. The embodiments disclosed herein may also be applicable toremote antenna clusters and distributed antenna systems and may alsoinclude more than one communications media for distribution ofcommunications signals (e.g., digital data services, RF communicationsservices).

Additional features and advantages will be set forth in the detaileddescription which follows, and in part, will be readily apparent tothose skilled in the art from that description or recognized bypracticing the embodiments as described herein, including the detaileddescription that follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description present embodiments, and are intendedto provide an overview or framework for understanding the nature andcharacter of the disclosure. The accompanying drawings are included toprovide a further understanding and are incorporated into and constitutea part of this specification. The drawings illustrate variousembodiments, and together with the description serve to explain theprinciples and operation of the concepts disclosed.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic of an exemplary conventional distributed antennasystem;

FIG. 2 is a schematic diagram of an exemplary distributed antenna systemhaving a downlink the extremely high frequency band;

FIG. 3 is graph of just noticeable difference versus transmitted powerfor various distances showing performance profiles for various possibleembodiments;

FIG. 4 is a schematic diagram of an alternate exemplary distributedantenna system having two data input sources;

FIG. 5 is a schematic diagram of an alternate exemplary embodimenthaving a plurality of remote antenna units;

FIG. 6 is a schematic diagram of an alternate exemplary embodiment withan uplink connection;

FIGS. 7A & 7B illustrate alternate methodologies for combining multipledata inputs;

FIG. 8 illustrates an exemplary distributed antenna system within abuilding;

FIG. 9 illustrates an exemplary alternate embodiment using an outdoorhigh definition input; and

FIG. 10 is a schematic diagram of a generalized representation of anexemplary computer system that can be included in any of the digitaldata sources, remote antenna units, client devices and/or other modulesprovided in the exemplary distributed antenna systems and/or theircomponents described herein, wherein the exemplary computer system isadapted to execute instructions from an exemplary computer readablemedium.

DETAILED DESCRIPTION

Reference will now be made in detail to the embodiments, examples ofwhich are illustrated in the accompanying drawings, in which some, butnot all embodiments are shown. Indeed, the concepts may be embodied inmany different forms and should not be construed as limiting herein;rather these embodiments are provided so that this disclosure willsatisfy applicable legal requirements. Whenever possible, like referencenumbers will be used to refer to like components or parts.

Embodiments disclosed in the detailed description include extremely highfrequency (EHF) (i.e., 30-300 GHz) distributed antenna systems, andrelated components, and methods. The systems disclosed herein cansupport provision of digital data services to wireless clients. The useof the EHF band allows for the use of channels having a higherbandwidth, which in turn allows more data intensive signals, such asuncompressed high definition (HD) video to be communicated withoutsubstantial degradation to the quality of the video. As a non-limitingexample, the distributed antenna systems disclosed herein may operate atapproximately sixty (60) GHz with approximately seven (7) GHz bandwidthchannels to provide greater bandwidth to digital data services. Thedistributed antenna systems disclosed herein may be well suited to bedeployed in an indoor building or other facility for delivering ofdigital data services.

In this regard, in one embodiment, a base unit for distributing EHFmodulated data signals to at least one remote antenna unit (RAU) isdisclosed. The base unit comprises a downlink data source inputconfigured to receive a downlink electrical data signal from a datasource. The base unit further comprises an electrical-to-optical (E-O)converter configured to convert the downlink electrical data signal intoa downlink optical data signal. The base unit further comprises anoscillator configured to generate an electrical carrier signal at acenter frequency in the EHF band. The base unit further comprises amodulator. The modulator is configured to combine the downlink opticaldata signal with the electrical carrier signal to form a downlinkmodulated optical signal comprising the downlink optical data signalmodulated at the center frequency of the electrical carrier signal. Themodulator is further configured to send the downlink modulated opticalsignal to at least one RAU.

Before discussing examples of EHF radio over fiber systems, components,and methods that support provision of digital data services to wirelessclients starting at FIG. 2, an exemplary distributed antenna system isdescribed with regards to FIG. 1. The distributed antenna system 10 ofFIG. 1 allows for distribution of radio frequency (RF) communicationssignals; however, the distributed antenna systems are not limited todistribution of RF communications signals. Also note that while thedistributed antenna system in FIG. 1 discussed below includesdistribution of communications signals over optical fiber, thesedistributed antenna systems are not limited to distribution over opticalfiber. Distribution media could also include, but are not limited to,coaxial cable, twisted-pair conductors, wireless transmission andreception, and any combination thereof. Also, any combination can beemployed that also involves optical fiber for portions of thedistributed system.

In this regard, FIG. 1 is a schematic diagram of a conventionaldistributed antenna system 10. The distributed antenna system 10 is anoptical fiber-based distributed antenna system. The distributed antennasystem 10 is configured to create one or more antenna coverage areas forestablishing communications with wireless client devices located in theRF range of the antenna coverage areas. In an exemplary embodiment, thedistributed antenna system 10 may provide RF communication services(e.g., cellular services). As illustrated, the distributed antennasystem 10 includes head-end equipment (HEE) 12 such as a head-end unit(HEU), one or more RAU 14, and an optical fiber 16 that opticallycouples the HEE 12 to the RAU 14. The RAU 14 is a type of remotecommunications unit. In general, a remote communications unit cansupport wireless communications or wired communications, or both. TheHEE 12 is configured to receive communications over downlink electricalRF signals 18D from a source or sources, such as a network or carrier asexamples, and provide such communications to the RAU 14. The HEE 12 isalso configured to return communications received from the RAU 14, viauplink electrical RF signals 18U, back to the source or sources. In thisregard, in this embodiment, the optical fiber 16 includes at least onedownlink optical fiber 16D to carry signals communicated from the HEE 12to the RAU 14 and at least one uplink optical fiber 16U to carry signalscommunicated from the RAU 14 back to the HEE 12.

One downlink optical fiber 16D and one uplink optical fiber 16U could beprovided to support full-duplex multiple channels each usingwave-division multiplexing (WDM), as discussed in U.S. patentapplication Ser. No. 12/892,424, entitled “Providing Digital DataServices in Optical Fiber-based Distributed Radio Frequency (RF)Communications Systems, And Related Components and Methods,”incorporated herein by reference in its entirety. Other options for WDMand frequency-division multiplexing (FDM) are also disclosed in U.S.patent application Ser. No. 12/892,424, any of which can be employed inany of the embodiments disclosed herein. Further, U.S. patentapplication Ser. No. 12/892,424 also discloses distributed digital datacommunications signals in a distributed antenna system which may also bedistributed in the distributed antenna system 10 either in conjunctionwith RF communications signals or not.

The distributed antenna system 10 has an antenna coverage area 20 thatcan be disposed about the RAU 14. The antenna coverage area 20 of theRAU 14 forms an RF coverage area 21. The HEE 12 is adapted to perform orto facilitate any one of a number of Radio-over-Fiber (RoF)applications, such as RF identification (RFID), wireless local-areanetwork (WLAN) communication, or cellular phone service. Shown withinthe antenna coverage area 20 is a client device 24 in the form of amobile device as an example, which may be a cellular telephone as anexample. The client device 24 can be any device that is capable ofreceiving RF communications signals. The client device 24 includes anantenna 26 (e.g., a wireless card) adapted to receive and/or sendelectromagnetic RF signals.

With continuing reference to FIG. 1, to communicate the electrical RFsignals over the downlink optical fiber 16D to the RAU 14, to in turn becommunicated to the client device 24 in the antenna coverage area 20formed by the RAU 14, the HEE 12 includes a radio interface in the formof an electrical-to-optical (E-O) converter 28. The E-O converter 28converts the downlink electrical RF signals 18D to downlink optical RFsignals 22D to be communicated over the downlink optical fiber 16D. TheRAU 14 includes an optical-to-electrical (O-E) converter 30 to convertthe received downlink optical RF signals 22D back to electrical RFsignals to be communicated wirelessly through an antenna 32 of the RAU14 to client device 24 located in the antenna coverage area 20.

Similarly, the antenna 32 is also configured to receive wireless RFcommunications from client device 24 in the antenna coverage area 20. Inthis regard, the antenna 32 receives wireless RF communications fromclient device 24 and communicates electrical RF signals representing thewireless RF communications to an E-O converter 34 in the RAU 14. The E-Oconverter 34 converts the electrical RF signals into uplink optical RFsignals 22U to be communicated over the uplink optical fiber 16U. An O-Econverter 36 provided in the HEE 12 converts the uplink optical RFsignals 22U into uplink electrical RF signals, which can then becommunicated as uplink electrical RF signals 18U back to a network orother source.

As noted, one or more of the network or other sources can be a cellularsystem, which may include a base station or base transceiver station(BTS). The BTS may be provided by a second party such as a cellularservice provider, and can be co-located or located remotely from the HEE12.

In a typical cellular system, for example, a plurality of BTSs aredeployed at a plurality of remote locations to provide wirelesstelephone coverage. Each BTS serves a corresponding cell and when amobile client device enters the cell, the BTS communicates with themobile client device. Each BTS can include at least one radiotransceiver for enabling communication with one or more subscriber unitsoperating within the associated cell. As another example, wirelessrepeaters or bi-directional amplifiers could also be used to serve acorresponding cell in lieu of a BTS. Alternatively, radio input could beprovided by a repeater, picocell, or femtocell as other examples. In aparticular exemplary embodiment, cellular signal distribution in thefrequency range from 400 MHz to 2.7 GHz is supported by the distributedantenna system 10.

It may be desirable to provide distributed antenna systems that providedigital data services for client devices. For example, it may bedesirable to provide digital data services to client devices locatedwithin a distributed antenna system. Wired and wireless devices may belocated in the building infrastructures that are configured to accessdigital data services. Examples of digital data services include, butare not limited to, Ethernet, WLAN, WiMax, WiFi, DSL, and LT, etc.Ethernet standards could be supported, including but not limited to 100Mb/s (i.e., fast Ethernet) or Gigabit (Gb) Ethernet, or ten Gigabit (10G) Ethernet. Examples of digital data services include, but are notlimited to, wired and wireless servers, wireless access points (WAPs),gateways, desktop computers, hubs, switches, remote radio heads (RRHs),baseband units (BBUs), and femtocells. A separate digital data servicesnetwork can be provided to provide digital data services to digital datadevices.

It may also be desired to provide high-speed wireless digital dataservice connectivity with RAUs in a distributed antenna system. Oneexample would be WiFi. WiFi was initially limited in data rate transferto 12.24 Mb/s and is provided at data transfer rates of up to 54 Mb/susing WLAN frequencies of 2.4 GHz and 5.8 GHz. While interesting formany applications, WiFi has proven to have too small a bandwidth tosupport real time downloading of uncompressed high definition (HD)television signals to wireless client devices. To increase data transferrates, the frequency of wireless signals could be increased to providelarger channel bandwidth. For example, an extremely high frequency inthe range of 30 GHz to 300 GHz could be employed. For example, the sixty(60) GHz spectrum is an EHF that is an unlicensed spectrum by theFederal Communications Commission (FCC) and that could be employed toprovide for larger channel bandwidths. However, high frequency wirelesssignals are more easily attenuated or blocked from traveling throughwalls or other building structures where distributed antenna systems areinstalled.

In this regard, FIG. 2 provides an exemplary distributed antenna system40 that is configured to support broad band digital data services suchas streaming HD video. In this regard, the distributed antenna system 40includes a base unit 50. The base unit 50 has a downlink data sourceinput 52 configured to receive a downlink data signal 53D from a datasource 54. In an exemplary embodiment, the downlink data signal 53D isan electrical signal, although it could be optical, wireless, or in someother format as desired. In a further exemplary embodiment, the datasource 54 is a high definition (HD) video data source and the downlinkdata signal 53D is a HD video signal. The data source 54 may be local orremote from the base unit 50. The base unit 50 receives the downlinkdata signal 53D through the downlink data source input 52 and convertsthe downlink data signal 53D to an optical signal using an E-O converter56. In an exemplary embodiment, the E-O converter 56 may be a laserdiode (LD) to form a downlink optical data signal 57D. In anotherexemplary embodiment, the E-O converter 56 may be a Mach-Zehnderelectro-optic device.

With continuing reference to FIG. 2, the downlink optical data signal57D is passed to an intensity modulator (IM) 58, which also receives anelectrical carrier signal 59D from a local oscillator 60. The electricalcarrier signal 59D is, in an exemplary embodiment, in the extremely highfrequency range (i.e., 30 GHz-300 GHz) and in a further embodiment isapproximately sixty (60) GHz. While FIG. 2 illustrates the localoscillator 60 as being positioned within the base unit 50, in analternate embodiment, the local oscillator 60 may be remotelypositioned. The intensity modulator 58 modulates the downlink opticaldata signal 57D with the electrical carrier signal 59D to create adownlink modulated optical signal 61D. The base unit 50 sends thedownlink modulated optical signal 61D through an optical fiber 62 to oneor more RAUs 64 (only one illustrated).

With continuing reference to FIG. 2, the RAU 64 receives the downlinkmodulated optical signal 61D and converts the downlink modulated opticalsignal 61D to a downlink modulated electromagnetic signal 70D using anoptical-to-electrical (O-E) converter 66, which, in an exemplaryembodiment, is a photodiode. The downlink modulated electromagneticsignal 70D is then transmitted through an antenna 68 to one or moreclient devices 24 such as a mobile terminal 24A or a wireless enabledcomputer 24B. While not illustrated in FIG. 2, but illustrated in FIG.4, the RAU 64 may include a low noise amplifier (LNA) to boost thesignal prior to transmission through the antenna 68. In an exemplaryembodiment, the wireless enabled computer 24B is equipped with anantenna 24B′ to facilitate reception of the downlink modulatedelectromagnetic signal 70D as is well understood.

In the client device 24, the downlink modulated electromagnetic signal70D is down-converted using a local oscillator operating at the carrierfrequency, and the downlink data signal 53D is recovered and used asdesired within the client device 24.

By providing the downlink modulated optical signal 61D in this manner,the downlink modulated electromagnetic signal 70D is also in the EHFband. Because of the nature of the distributed antenna system, thedistance between the client device 24 and the RAU 64 is relatively small(e.g., <10 meters). Because typical channel width in the sixty (60) GHzrange is seven (7) GHz, there is sufficient bandwidth to accommodatelarge data files or streaming data such as a HD video signal.

Empirical testing also indicates that this system performs better than adirectly-modulated mm-wave radio over fiber system because the frequencyresponse is dominated by the low-frequency response of the O-E converter56. The high-speed modulator only impacts the link efficiency, and itsfrequency response has no impact on the overall frequency response ofthe link. Further, empirical testing reveals that no optical signalfiltering is required for fiber spans in the range of five hundred (500)meters, which should be sufficient for most distributed antenna systems.Further note that in the broadcast mode, no uplink signal is required.Thus, conventional receivers could be eliminated from the base unit 50and the RAU 64 if desired for such a system.

In specific exemplary testing, an uncompressed HD video signal was sentat various optical power levels, and the video quality at the clientdevice 24 was evaluated using the just noticeable difference (JND)values. The results of this testing are presented as graph 42 in FIG. 3.It is generally accepted that JND values below 5 are consideredacceptable. As is apparent from the data in FIG. 3, it is not difficultto achieve acceptable video signal transmission at ranges of ten metersfrom the RAU 64 at acceptable power levels.

FIG. 4 illustrates an alternate embodiment of a distributed antennasystem 44 configured to support and distribute EHF communicationssignals. In this embodiment, the distributed antenna system 44 isconfigured to receive data input from a plurality of sources. In thisregard, the downlink data source input 52 is configured to receive datainput from a plurality of sources 54 such as HD video source 54A anddata source 54B. The plurality of data sources 54 may be accommodated byhaving multiple ports on the base unit 50 or by having a combinercombine the signals from the data sources 54 into a single signal forthe base unit 50. Further, in FIG. 4, the downlink data is provided on asingle optical fiber 62.

An alternate embodiment of a distributed antenna system 46 isillustrated in FIG. 5, wherein a plurality of optical fibers 62 is usedso that a plurality of RAU 64 may receive optical signals. Thisarrangement allows a plurality of RAU 64 to receive optical signals. Inan exemplary embodiment, the plurality of optical fibers 62 are arrangedin an array cable 70, such as is used for in-building distribution ofRAUs 64. A 1-to-N fiber splitter 72 may be used to separate the signalsas desired onto the array cable 70.

FIG. 6 illustrates another alternate embodiment of a distributed antennasystem 48 configured to support and distribute EHF communicationssignals. In this embodiment, there is an uplink connection from theremote client so as to allow bi-directional communication. That is,there is an uplink connection between the client device 24 and the baseunit 50. In an exemplary embodiment, the uplink occurs at asubstantially lower frequency than the downlink frequency. Because EHFoperation may be power intensive and because the uplink signalstypically do not contain large data packets, the uplink communicationsdo not need to take place in the EHF band. Thus, conventional WiFi,WLAN, BLUETOOTH®, or other comparatively low frequency technologies maybe used for the uplink signal.

In practice, the base unit 50 remains largely unchanged, but a receiver80 is added. The receiver 80 may be positioned within the base unit 50(illustrated), within an RAU 64 (not illustrated), or positionedremotely from the base unit 50 and the RAU 64, as desired. The receiver80 is configured to receive uplink signal 81U through an antenna 82. Thereceiver 80 may further pass an uplink signal 83U to the data source 54,or other element within the system as desired.

Similarly, the client device 24C remains essentially unchanged on thedownlink side from the previously described client device 24 in that thewireless client 24C receives the downlink modulated electromagneticsignal 70D through an antenna 84 with an EHF (e.g., 60 GHz) receiver 86,and downconverts the EHF signal using a local oscillator 88 andmanipulates the embedded data as desired (e.g., plays HD video on adisplay). However, the client device 24C also includes a wirelesstransmitter 90, which transmits the uplink signal 81U through an antenna92. Because EHF operation may be power intensive and because the uplinksignals typically do not contain large data packets, the uplinkcommunications do not need to take place in the EHF band. Thus,conventional WiFi, WLAN, BLUETOOTH®, or other comparatively lowfrequency technologies may be used for the uplink signal. As used hereinthe term “substantially lower than 60 GHz” or “substantially lower thanEHF” is defined to be a frequency lower than 15 GHz. It should beappreciated that if there are multiple wireless clients 24 sendinguplink signals 81U, then the receiver 80 is configured to receive suchplurality of signals.

FIGS. 7A and 7B illustrate two alternate ways that multiple data signalsmay be multiplexed onto the single optical fiber 62 of the previousembodiments. In FIG. 7A, a N×1 switch 94 allows 1-to-N data sources54A-54N to be coupled to the optical fiber 62. In FIG. 7B, a sub carriermultiplexing (SCM) switch 96 may be used. Still other techniques may beused as desired. Note that with 7 GHz channels, as a non-limitingexample, it may be possible to have three (3) uncompressed HD videosources as inputs.

The system of the present disclosure has numerous applications, two ofwhich are explicitly set forth with reference to FIGS. 8 and 9. In FIG.8, a distributed antenna system according to the present disclosure,such as systems 40, 44, 46, or 48 can be configured to support anddistribute EHF communications signals. In this embodiment, the system isinstalled in a building 100 and an outbuilding 102 so that remoteclients may receive RF communications signals. A fiber optic cable 62 isan array cable and is coupled to a base unit 50 which may be positionedoutside or remote from the building 100. The optical fiber 62 isconnected to a plurality of RAUs 64 distributed throughout the building100 and outbuilding 102. A splitter 104 allows the optical fiber 62 tobe split as desired to extend the run to the outbuilding 102. Aplurality of clients devices 24 are positioned within range of the RAUs64 and can stream HD video signals or other data signals as desired. Inthis manner, users of client devices 24 may receive broad band digitaldata signals such as HD video signals despite the presence of the wallsof the building 100 or outbuilding 102 which might otherwise attenuatesuch signals.

In FIG. 9, a plurality of HD cameras 106 are effectively base units,coupled via respective optical fibers 62 to respective RAUs 64. The RAUs64 transmit the signal to a processing station 108. As illustrated, theprocessing station 108 receives the three illustrated signals andcombines them using a SCM 96, and conveys the combined signal tocircuitry where the signals may be manipulated. Thus, the concepts ofthe present disclosure can be metaphorically inverted such that insteadof downloading broad band digital data to a remote client, a pluralityof remote cameras 106 may upload broadband digital data (e.g., an HDvideo signal) to a processing station 108.

FIG. 10 is a schematic diagram representation of additional detailregarding an exemplary RAU 64, client device 24 and/or elements adaptedto execute instructions from an exemplary computer-readable medium toperform the location services described herein. In this regard, the RAU64 or other element may include a computer system 140 within which a setof instructions for performing any one or more of the location servicesdiscussed herein may be executed. The computer system 140 may beconnected (e.g., networked) to other machines in a LAN, an intranet, anextranet, or the Internet. The computer system 140 may operate in aclient-server network environment, or as a peer machine in apeer-to-peer (or distributed) network environment. While only a singledevice is illustrated, the term “device” shall also be taken to includeany collection of devices that individually or jointly execute a set (ormultiple sets) of instructions to perform any one or more of themethodologies discussed herein. The computer system 140 may be a circuitor circuits included in an electronic board card, such as a printedcircuit board (PCB) as an example, a server, a personal computer, adesktop computer, a laptop computer, a personal digital assistant (PDA),a computing pad, a mobile device, or any other device, and mayrepresent, for example, a server or a user's computer.

The exemplary computer system 140 in this embodiment includes aprocessing device or processor 142, a main memory 144 (e.g., read-onlymemory (ROM), flash memory, dynamic random access memory (DRAM) such assynchronous DRAM (SDRAM), etc.), and a static memory 146 (e.g., flashmemory, static random access memory (SRAM), etc.), which may communicatewith each other via the data bus 148. Alternatively, the processingdevice 142 may be connected to the main memory 144 and/or static memory146 directly or via some other connectivity means. The processing device142 may be a controller, and the main memory 144 or static memory 146may be any type of memory.

The processing device 142 represents one or more general-purposeprocessing devices such as a microprocessor, central processing unit, orthe like. More particularly, the processing device 142 may be a complexinstruction set computing (CISC) microprocessor, a reduced instructionset computing (RISC) microprocessor, a very long instruction word (VLIW)microprocessor, a processor implementing other instruction sets, orprocessors implementing a combination of instruction sets. Theprocessing device 142 is configured to execute processing logic ininstructions 150 for performing the operations and steps discussedherein.

The computer system 140 may further include a network interface device152. The computer system 140 also may or may not include an input 154 toreceive input and selections to be communicated to the computer system140 when executing instructions. The computer system 140 also may or maynot include an output 156, including but not limited to a display, avideo display unit (e.g., a liquid crystal display (LCD) or a cathoderay tube (CRT)), an alphanumeric input device (e.g., a keyboard), and/ora cursor control device (e.g., a mouse).

The computer system 140 may or may not include a data storage devicethat includes instructions 158 stored in a computer-readable medium 160.The instructions 158 may also reside, completely or at least partially,within the main memory 144 and/or within the processing device 142during execution thereof by the computer system 140, the main memory 144and the processing device 142 also constituting computer-readablemedium. The instructions 158 may further be transmitted or received overa network 162 via the network interface device 152.

While the computer-readable medium 160 is shown in an exemplaryembodiment to be a single medium, the term “computer-readable medium”should be taken to include a single medium or multiple media (e.g., acentralized or distributed database, and/or associated caches andservers) that store the one or more sets of instructions. The term“computer-readable medium” shall also be taken to include any mediumthat is capable of storing, encoding, or carrying a set of instructionsfor execution by the processing device and that cause the processingdevice to perform any one or more of the methodologies of theembodiments disclosed herein. The term “computer-readable medium” shallaccordingly be taken to include, but not be limited to, solid-statememories, optical and magnetic medium, and carrier wave signals.

The embodiments disclosed herein include various steps. The steps of theembodiments disclosed herein may be formed by hardware components or maybe embodied in machine-executable instructions, which may be used tocause a general-purpose or special-purpose processor programmed with theinstructions to perform the steps. Alternatively, the steps may beperformed by a combination of hardware and software.

The embodiments disclosed herein may be provided as a computer programproduct, or software, that may include a machine-readable medium (orcomputer-readable medium) having stored thereon instructions, which maybe used to program a computer system (or other electronic devices) toperform a process according to the embodiments disclosed herein. Amachine-readable medium includes any mechanism for storing ortransmitting information in a form readable by a machine (e.g., acomputer). For example, a machine-readable medium includes amachine-readable storage medium (e.g., ROM, random access memory(“RAM”), magnetic disk storage medium, optical storage medium, flashmemory devices, etc.), a machine readable transmission medium(electrical, optical, acoustical, or other form of propagated signals(e.g., carrier waves, infrared signals, digital signals, etc.)), etc.

Unless specifically stated otherwise as apparent from the previousdiscussion, it is appreciated that throughout the description,discussions utilizing terms such as “processing,” “computing,”“determining,” “displaying,” or the like refer to the action andprocesses of a computer system, or similar electronic computing device,that manipulates and transforms data represented as physical(electronic) quantities within the computer system's registers andmemories into other data similarly represented as physical quantitieswithin the computer system memories or registers or other suchinformation storage, transmission, or display devices.

The algorithms and displays presented herein are not inherently relatedto any particular computer or other apparatus. Various systems may beused with programs in accordance with the teachings herein, or it mayprove convenient to construct more specialized apparatuses to performthe required method steps. The required structure for a variety of thesesystems will appear from the description above. In addition, theembodiments described herein are not described with reference to anyparticular programming language. It will be appreciated that a varietyof programming languages may be used to implement the teachings of theembodiments as described herein.

Those of skill in the art would further appreciate that the variousillustrative logical blocks, modules, circuits, and algorithms describedin connection with the embodiments disclosed herein may be implementedas electronic hardware, instructions stored in memory or in anothercomputer-readable medium and executed by a processor or other processingdevice, or combinations of both. The components of the distributedantenna systems described herein may be employed in any circuit,hardware component, integrated circuit (IC), or IC chip, as examples.Memory disclosed herein may be any type and size of memory and may beconfigured to store any type of information desired. To clearlyillustrate this interchangeability, various illustrative components,blocks, modules, circuits, and steps have been described above generallyin terms of their functionality. How such functionality is implementeddepends on the particular application, design choices, and/or designconstraints imposed on the overall system. Skilled artisans mayimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentembodiments.

The various illustrative logical blocks, modules, and circuits describedin connection with the embodiments disclosed herein may be implementedor performed with a processor, a Digital Signal Processor (DSP), anApplication Specific Integrated Circuit (ASIC), a Field ProgrammableGate Array (FPGA), or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described herein. A controllermay be a processor. A processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The embodiments disclosed herein may be embodied in hardware and ininstructions that are stored in hardware, and may reside, for example,in RAM, flash memory, ROM, Electrically Programmable ROM (EPROM),Electrically Erasable Programmable ROM (EEPROM), registers, a hard disk,a removable disk, a CD-ROM, or any other form of computer-readablemedium known in the art. An exemplary storage medium is coupled to theprocessor such that the processor can read information from, and writeinformation to, the storage medium. In the alternative, the storagemedium may be integral to the processor. The processor and the storagemedium may reside in an ASIC. The ASIC may reside in a remote station.In the alternative, the processor and the storage medium may reside asdiscrete components in a remote station, base station, or server.

It is also noted that the operational steps described in any of theexemplary embodiments herein are described to provide examples anddiscussion. The operations described may be performed in numerousdifferent sequences other than the illustrated sequences. Furthermore,operations described in a single operational step may actually beperformed in a number of different steps. Additionally, one or moreoperational steps discussed in the exemplary embodiments may becombined. Those of skill in the art would also understand thatinformation and signals may be represented using any of a variety oftechnologies and techniques. For example, data, instructions, commands,information, signals, bits, symbols, and chips that may be referencesthroughout the above description may be represented by voltages,currents, electromagnetic waves, magnetic fields, or particles, opticalfields or particles, or any combination thereof.

Further, as used herein, it is intended that terms “fiber optic cables”and/or “optical fibers” include all types of single mode and multi-modelight waveguides, including one or more optical fibers that may beupcoated, colored, buffered, ribbonized, and/or have other organizing orprotective structure in a cable such as one or more tubes, strengthmembers, jackets, or the like. The optical fibers disclosed herein canbe single mode or multi-mode fibers. Likewise, other types of suitableoptical fibers include bend-insensitive optical fibers, or any otherexpedient of a medium for transmitting light signals. An example of abend-insensitive, or bend resistant, optical fiber is ClearCurve®Multimode fiber commercially available from Corning Incorporated.Suitable fibers of this type are disclosed, for example, in U.S. PatentApplication Publication Nos. 2008/0166094 and 2009/0169163, thedisclosures of which are incorporated herein by reference in theirentireties.

Many modifications and other embodiments of the embodiments set forthherein will come to mind to one skilled in the art to which theembodiments pertain having the benefit of the teachings presented in theforgoing descriptions and the associated drawings.

Therefore, it is to be understood that the description and claims arenot to be limited to the specific embodiments disclosed, and thatmodifications and other embodiments are intended to be included withinthe scope of the appended claims. It is intended that the embodimentscover the modifications and variations of the embodiments provided theycome within the scope of the appended claims and their equivalents.Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation.

What is claimed is:
 1. A system for distributing extremely highfrequency (EHF) modulated data signals to a plurality of remote antennaunits (RAUs) deployed in a building infrastructure, the systemcomprising: a downlink data source input configured to receive adownlink electrical data signal from a data source, the downlinkelectrical signals including at least one high definition video signal;an electrical-to-optical (E-O) converter configured to convert thedownlink electrical data signal into a downlink optical data signal; anoscillator configured to generate an electrical carrier signal at acenter frequency in an EHF band between 30 and 300 GHz; a modulatorconfigured to combine the downlink optical data signal with theelectrical carrier signal to form a downlink modulated optical signalcomprising the downlink optical data signal modulated at the centerfrequency of the electrical carrier signal; and a plurality of RAUsdistributed in the building infrastructure, at least one RAU beingoptically coupled to the E-O converter and comprising: an optical toelectrical (O-E) converter configured to receive the downlink modulatedoptical signal from the modulator and convert the downlink modulatedoptical signal into a downlink modulated electrical signal, and one ormore antennas configured to transmit the downlink modulated electricalsignal as an electromagnetic signal to a wireless client, and to receiveWireless Fidelity (WiFi) uplink electromagnetic signals from a wirelessclient.
 2. The system of claim 1, wherein at least one RAU is opticallycoupled to the E-O converter by at least one optical fiber, the centerfrequency is approximately 60 GHz, and a channel width associated withthe downlink modulated optical signal is approximately 7 GHz.
 3. Thesystem of claim 1, further comprising at least one of a subcarriermultiplexing switch and an N×1 switch configured to multiplex from 1 toN data sources.
 4. A system for distributing extremely high frequency(EHF) modulated data signals to a plurality of remote antenna units(RAUs) deployed in a building infrastructure, the system comprising: adownlink data source input configured to receive downlink electricaldata signals from a plurality of data sources, the downlink electricalsignals including at least one high definition video signal; a switchconfigured to multiplex the downlink electrical data signals; anelectrical-to-optical (E-O) converter configured to convert at least oneof the downlink electrical data signals into at least one downlinkoptical data signal; an oscillator configured to generate an electricalcarrier signal at a center frequency in a EHF band between 30 and 300GHz; a modulator configured to combine the at least one downlink opticaldata signal with the electrical carrier signal to form a downlinkmodulated optical signal comprising the downlink optical data signalmodulated at the center frequency of the electrical carrier signal; anda plurality of RAUs distributed in the building infrastructure, at leastone RAU being optically coupled to the E-O converter and comprising: anoptical to electrical (O-E) converter configured to receive the downlinkmodulated optical signal from the modulator and convert the downlinkmodulated optical signal into a downlink modulated electrical signal,and one or more antennas configured to transmit the downlink modulatedelectrical signal as an electromagnetic signal to a wireless client, andto receive uplink electromagnetic signals at frequencies substantiallylower than 30 GHz from a wireless client.
 5. The system of claim 4,wherein at least one RAU is optically coupled to the E-O converter by atleast one optical fiber, the center frequency is approximately 60 GHz,and a channel width associated with the downlink modulated opticalsignal is approximately 7 GHz.
 6. The system of claim 4, wherein theuplink electromagnetic signals at frequencies substantially lower than30 GHz are lower than 15 GHz.
 7. A method for distributing extremelyhigh frequency (EHF) modulated data signals via a plurality of remoteantenna units (RAUs) deployed in a building infrastructure, the methodcomprising: receiving a downlink electrical data signal from a downlinkdata source, wherein receiving the downlink electrical data signal fromthe downlink data source comprises receiving at least one highdefinition video signal; converting the downlink electrical data signalinto a downlink optical data signal; combining the downlink optical datasignal with an electrical carrier signal operating in an EHF bandbetween 30 and 300 GHz to form a downlink modulated optical signalcomprising the downlink optical data signal modulated at a centerfrequency of the electrical carrier signal; and sending the downlinkmodulated optical signal to at least one RAU of the plurality of RAUs;and, at the at least one RAU: converting the downlink modulated opticalsignal into a downlink modulated electromagnetic signal; transmittingthe downlink modulated electromagnetic signal to a wireless clientwithin the infrastructure; and receiving Wireless Fidelity (WiFi) uplinkelectromagnetic signals from a wireless client within theinfrastructure.
 8. The method of claim 7, wherein receiving a downlinkelectrical data signal from a downlink data source comprises receivingmultiple downlink electrical signals, the method further comprisingmultiplexing the downlink electrical signals.
 9. A system fordistributing extremely high frequency (EHF) modulated data signals to aplurality of remote antenna units (RAUs) deployed in an infrastructure,the system comprising: a downlink data source input configured toreceive a downlink electrical data signal from a data source, thedownlink electrical signals including at least one video signal; anelectrical-to-optical (E-O) converter configured to convert the downlinkelectrical data signal into a downlink optical data signal; anoscillator configured to generate an electrical carrier signal at acenter frequency in an EHF band between 30 and 300 GHz; a modulatorconfigured to combine the downlink optical data signal with theelectrical carrier signal to form a downlink modulated optical signalcomprising the downlink optical data signal modulated at the centerfrequency of the electrical carrier signal; and a plurality of RAUsdistributed in the building infrastructure, at least one RAU beingoptically coupled to the E-O converter by at least one optical fibercable, the at least one RAU comprising: an optical to electrical (O-E)converter configured to receive the downlink modulated optical signalfrom the modulator and convert the downlink modulated optical signalinto a downlink modulated electrical signal, and at least one antennaconfigured to transmit the downlink modulated electrical signal as anelectromagnetic signal to a wireless client, and to receive uplinkelectromagnetic signals from a wireless client at a frequency lower than15 GHz.
 10. The system of claim 9, wherein the uplink electromagneticsignals include Wireless Fidelity (WiFi) signals.
 11. The system ofclaim 10, further comprising a plurality of high definition (HD) videosources, and at least one of a subcarrier multiplexing switch and an N×1switch configured to multiplex the HD video sources.
 12. A system fordistributing extremely high frequency (EHF) signals to a plurality ofremote antenna units (RAUs) deployed in an infrastructure, the systemcomprising: a plurality of high definition (HD) video sources; adownlink data source input configured to receive a downlink electricaldata signal from the HD video sources; an electrical-to-optical (E-O)converter configured to convert the downlink electrical data signal intoa downlink optical data signal; an oscillator configured to generate anelectrical carrier signal at a center frequency in an EHF band between30 and 300 GHz; a modulator configured to combine the downlink opticaldata signal with the electrical carrier signal to form a downlinkmodulated optical signal comprising the downlink optical data signalmodulated at the center frequency of the electrical carrier signal; anda plurality of RAUs distributed in the building infrastructure, at leastone RAU being optically coupled to the E-O converter by at least oneoptical fiber, the at least one RAU comprising: an optical to electrical(O-E) converter configured to receive the downlink modulated opticalsignal from the modulator and convert the downlink modulated opticalsignal into a downlink modulated electrical signal, and at least oneantenna configured to transmit the downlink modulated electrical signalas an electromagnetic signal to a wireless client, and to receive uplinkelectromagnetic signals from a wireless client at a frequencysubstantially lower than the EHF band.